Adhesive optical film to convert an eyeglass lens to a progressive lens

ABSTRACT

Apparatus and methods are described including generating a multi-focal lens and/or a progressive lens by adhering a corrective optical film to an optically-corrective single-focal lens, such as to change a focal length of the single-focal lens differently in different regions of the single-focal lens. Other applications are also described.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. Ser. No. 15/310,356 toArieli (published as US 2017/0269379), which is a US national phaseapplication of PCT Application No. PCT/IL/2015/050475 to Arieli(published as WO 15/173797), entitled “Adhesive optical film to convertan eyeglass lens to a progressive lens,” filed May 7, 2015, which claimspriority from U.S. Provisional Patent Application 61/991,514 to Arieli,entitled “Adhesive optical film to convert an eyeglass lens to aprogressive lens,” filed May 11, 2014.

TECHNICAL FIELD

The present invention relates to multifocal ophthalmic lenses,progressive lenses, lens designs, eyeglasses. More specifically, thepresent invention relates to converting single vision lenses tomultifocal or progressive lenses.

BACKGROUND ART

Presbyopia is usually treated with multifocal eyeglasses, progressiveeyeglasses or contact lenses. Many methods for creating andmanufacturing of progressive lenses are known in the art, such aspolishing a semi-finished lens or molding. LASIK and other types ofsurgery cannot prevent or remedy this natural occurrence, whichgradually affects nearly everyone over age 40. The visual effects causedby Presbyopia may slowly worsen for several years, requiring new changesin lens prescription, but will stabilize by age 65 or 70.

Corrective lenses are used in eyeglasses to correct Presbyopia and otherdisorders of accommodation. A basic solution for Presbyopia is the useof multifocal spectacle lenses. Multifocal spectacle lenses contain twoor more lens powers to help you see objects at all distances. Bifocalscontain two lens powers; trifocals contain three.

Progressive spectacle lenses are characterized by a gradient ofincreasing lens power, added to the wearer's correction for the otherrefractive errors. The gradient starts at the wearer's distanceprescription, at the top of the lens and reaches a maximum additionpower, or the full reading addition, at the bottom of the lens. Theaddition in middle of the lens usually enables reading text on acomputer screen. The length of the progressive power gradient on thelens surface depends on the design of the lens, with a final additionpower between 0.75 and 3.50 diopters. The addition value prescribeddepends on the level of presbyopia of the patient.

The main disadvantages of multifocal eyeglasses and progressive lensesare their high cost and their need for professional adaptation.

There is thus required a method and system that provides a reasonablesolution for the Presbyopia problem, while keeping a very low price thatenables use of progressive lenses by everyone who needs it. Such asolution usually will not require a professional adaptation.

DESCRIPTION OF THE PRIOR ART

There are many means of converting conventional eyeglasses.

U.S. Pat. No. 2,511,329 describes a cover for a spectacle lensincluding, a thin flat sheet of tinted transparent materialsubstantially the size and shape of a lens, and an adhesive on one sideof the sheet, the sheet being weakened along a line establishing an areathat can be removed at will.

U.S. Pat. No. 2,759,394 describes a glare shield for a concave-convexlens, said shield comprising a thin, pre-formed, substantiallynon-stretchable self-supporting sheet of tinted transparent materialhaving uniform thickness and of no greater overall plan dimensions thansaid lens, said sheet comprising a narrow peripheral border portionpre-formed into a predetermined concave shape to conform to the convexsurface of said lens, the remaining central major portion of said sheetwithin the inner periphery of said border portion being curvablypre-formed to a concave curvature greater than the convex curvature ofsaid convex lens surface, whereby said central major portion is out ofcontact with said convex lens surface when said border portion is inconforming contact with said convex lens surface within the periphery ofsaid lens surface, a layer of pressure-sensitive adhesive on only thelens-engaging face of said border portion to removably adhere said sheetto said lens, and an upset portion of said border portion restricted inextent to lie within the peripheral boundaries of said sheet andpre-formed to stand upwardly out of the curved path established by theborder portion sufficiently to accept a fingernail thereunder betweensaid upset portion and said lens surface for the purpose of removingsaid sheet from lens, said upset portion providing by expansion latitudethe exact curvature of said border portion to fit lenses of slightlydiffering convex outer surface curvatures.

U.S. Pat. No. 3,628,854 describes a thin, fully conformable, plasticmembrane which can be applied, and made to adhere with finger pressure,to spectacle lenses for quickly and impermanent changing one or moreoptical characteristics of the spectacle lenses. The membrane may beembossed on one of its surfaces to form a Fresnel-type lens or prismstructure to introduce a deviation of the light ray, may be partially orentirely tinted to pass only certain wavelengths of light, may bediffused, or blurred uniformly or differentially, may have selectiveopaqued or transmitting areas or a combination thereof.

U.S. Pat. No. 5,764,333 describes a method and kit for making sunshieldsfor eyeglasses. The sunshields are flexible, transparent sheets ofsmooth plastic film that are retained on lenses of eyeglasses byelectrostatic attraction. The sunshields are made of smooth plastic filmhaving opposed parallel surfaces that are flat and planar except as thefilm may be curved to match surfaces of the lenses, and absorb someincident electromagnetic radiation. The method includes the steps oflaying eyeglasses on a sheet of writing material and tracing an outlineof lenses of the eyeglasses on the sheet with a writing implement,cutting along the outlines on the sheet to obtain silhouettes of thelenses, comparing the silhouettes to the lenses in the eyeglasses to seeif they match, and laying the silhouettes on a sheet of the smoothplastic film, and cutting the plastic film along the edges of thesilhouettes. Also included in the invention is a carrying case for thesunshields, having a material on its interior surface which can impartan electrostatic charge to the sunshields.

In U.S. Pat. No. 6,290,354, non-corrective eyewear such as sunglasses,skiing goggles and diving masks can be easily and economically made tocorrect eyesight with a corrective eyewear attachment that isaesthetically pleasing. The attachment may include a corrective nosepiece connector and/or a rotatable lens. The rotatable lens makes itmore economical to have prefabricated corrective lenses that requires aparticular lens orientation such as when the corrective lens correctsfor an astigmatism.

In U.S. Pat. No. 7,036,929, an apparatus and method for applying andremoving a disposable optical film to and from an eyeglass lens isdescribed. The disposable optical film of the invention has an adhesiveelement on one side for the removable attachment to an eyeglass lens.The adhesive element is protected by a peel and stick backing that hasindicia defining the parameters of the corrective film, thus allowingthe user to trim the corrective film to the appropriate size and shapeof a multiplicity of eyeglass styles without compromising the integrityof the corrective film.

None of the abovementioned provides a reasonable low cost solution forthe Presbyopia problem.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a methodand system that provides a reasonable low cost solution for visionproblems by applying an optical corrector sticker to a regular low costlens.

According to one embodiment of the present invention a progressive lens,made of a clear elastic material and implemented as a sticker is appliedon regular single-vision spectacles. Applying the sticker may be doneeither during lens production process, by a sales representative or bythe customer itself.

According to another embodiment of the present invention an opticalcorrector, made of a clear elastic material and implemented as a stickeris applied on regular single-vision spectacles to correct optical visionimpairments such as Astigmatism.

In order to understand the invention and to see how it may be carriedout in practice, embodiments will now be described, by way ofnon-limiting example only, with reference to the accompanying drawing,in which:

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a regular single-vision lens to which a correctiveoptical film is to be applied to convert it to a progressive or amultifocal lens.

FIG. 2a illustrates a typical cross section of one embodiment of acorrective optical film according to the present invention.

FIG. 2b illustrates a typical cross section of another embodiment of acorrective optical film according to the present invention.

FIG. 3 illustrates a corrective optical film of the present inventionincluding a transparent adhesive backing.

FIG. 4a illustrates a corrective optical film being protected with twofilms, one on each side.

FIG. 4b illustrates simple alignment mark on one of the protectionfilms.

FIG. 5a illustrates a cross section of the corrective optical filmattached to the outer surface of a regular single-vision lens.

FIG. 5b illustrates a cross section of the corrective optical filmattached to the inner surface of a regular single-vision lens.

FIG. 6a illustrates measuring of the largest distance to a target wherethe vision is still clear without blurring.

FIG. 6b illustrates measuring of the shortest distance to a target wherethe vision is still clear without blurring.

FIG. 7 illustrates marking points where the pupils of each eye arelocated.

DETAILED DESCRIPTION OF INVENTION

The following discussion describes in detail embodiments of the presentinvention. This should not be construed, however, as limiting theinvention to those particular embodiments since practitioners skilled inthe art will recognize numerous other embodiments as well.

FIG. 1 shows a regular single-vision lens 100 to which a correctiveoptical film 120 is to be applied to convert the regular single-visionlens to a progressive or a multifocal lens. The corrective film 120 madeof a clear elastic material and implemented as a sticker, is applied byusing transparent adhesive material on said regular single-vision lens100. The corrective optical film 120 may be attached to the frontsurface or the rear surface of the regular single-vision lens 100. Twoor more different corrective optical films may also be attached to thefront surface and the rear surface of the regular single-vision lens100. The single-vision lens 100 may be implemented as a transparentmaterial without any optical corrective value.

FIG. 2a and FIG. 2b show a typical cross section of the correctiveoptical film 120 according to two embodiments of the present invention.The optical film 120 may have different optical powers in differentregions to correct the focal length of a regular single-vision lensesdifferently. In one embodiment (FIG. 2a ) the film 120 may have a freeform. In another embodiment (FIG. 2b ) the film 120 may have discreteregions 121, 122 and 123 of different thicknesses and differentcurvatures in different places. Alternatively or in addition, the filmmay have a graded index profile which means different refractive indicesin different regions with a uniform or non-uniforms thicknesses andcurvature in order to have different optical powers to change the focallengths of the said regular single-vision lenses differently indifferent regions. The graded index profile may be produced according toany known method known in the industry, such as Partial polymerizationby UV light, Neutron irradiation or Chemical vapor deposition. Thecorrective optical film 120 may be disposable or have a life time-limit,and may include other elements such as anti-glare and/or anti-scratchcoating, and/or UV protective materials, and/or other additional opticalfunctionalities as currently known in the art.

FIG. 3 shows the corrective optical film 120 of the present inventionincluding a transparent adhesive backing 130 to adhere the film to thelens to be converted to a progressive or multifocal lens. The adhesivebacking may be a permanent or a peel-off adhesive backing, aself-sticking backing with a spray-on mist or any other suitable backingwith a spray-on mist or any other suitable means to effectively adherethe film to the said lens. Furthermore, in order that the adhesive sidedoesn't prematurely stick on the sunglasses, a spray of water can beapplied in order to position the film before it is in place.

FIG. 4a and FIG. 4b describe the corrective optical film 120 of thepresent invention when being protected with two films 200 and 210, oneon each side. Protection film 200 protects the adhesive substance 130and is removed just before applying the corrective optical film 120 tothe said single-vision lens. Protection film 210 protects the outer sideof the corrective optical film 120 and is usually removed after applyingthe corrective optical film 120 to the said single-vision lens in asimilar process which is commonly used to apply anti-scratch screenprotector for a cellular phone. On the protection film 210 there may bealignment mark 220 that its purpose is to accommodate the correctiveoptical film 120 to the right location on the lens to be corrected.Other marks may indicate areas which should not be cut, to preventdamage to the optical areas of the corrective optical film 120. In caseprotective film is not used, such erasable marks will appear directly onthe corrective optical film 120 itself and will be erased after applyingthe corrective optical film 120 to the eyeglasses lens 100.

FIG. 5a and FIG. 5b show a cross section of the corrective optical film120 attached to the regular single-vision lens 100 to be converted to aprogressive or a multifocal lens. In one embodiment according to thepresent invention (FIG. 5a ) the corrective optical film 120 is attachedto the outer side of the regular single-vision lens 100 (far from thepatient's eye). In another embodiment according to the present invention(FIG. 5b ) the corrective optical film 120 is attached to the inner sideof the regular single-vision lens 100 (between the patient's eye and thelens). The single-vision lens 100 must be at a minimal size to enabledifferent optical regions in a multifocal lens, and the film 120 willusually be larger than the single-vision lens 100. In such case, thefilm 120 is cut to accommodate the size and shape of the lens on whichit is to be installed. The film 120 may be cut before or after applyingit to the lens. In another embodiment of the present invention, the film120 may come in pre-defined sizes adapted for specific common models andstyles of eyeglasses, and therefore the need to cut it will beeliminated.

FIGS. 6a and 6b show a method for accommodating the proper correctiveoptical films to two single-vision lenses 300 and 320 of eyeglasses 350in order to convert said two single-vision lenses to progressive ormultifocal lenses. The customer 250 who wears said eyeglasses 350 withsingle-vision lenses has to do two examinations. One examination is tomeasure the largest distance 410 to the target 400 that he still hasclear vision without blurring (FIG. 6a ). The second examination is tomeasure the smallest distance 420 to the target 400 that he still hasclear vision without blurring (FIG. 6b ). These two examinations have tobe done for each eye while wearing the eyeglasses. From these two setsof distances 410 and 420 the proper corrective optical films for eacheye are chosen.

FIG. 7 shows a method for matching the corrective optical films to theproper location on each of the single-vision lenses to be converted toprogressive or multifocal lenses. The customer 250 who wears saideyeglasses 350 with said single-vision lenses to be converted, has tolook with both eyes to a single point target 400 located at knowndistance. The customer itself or a sales representative should mark withan erasable marker on each lens of the eyeglasses a point 450 and 460where each pupil of each eye is located. When the corrective film isapplied to each lens to be converted, this mark is matched to thealignment mark 220 on the protection film 210 (FIG. 4a and FIG. 4b ).When the corrective film is applied to the rear surface of the lens thepoint 450 is marked on the front surface of the lens and vice versa.After completing the alignment, all marks required for the alignment maybe erased. When using protective film 210 on the outer side of thecorrective optical film, the removal of this protective film will alsoremove the alignment marks and leave the corrective film clear of anymarks.

1. Apparatus comprising: an optically-corrective single-focal lens; anda corrective optical film, a characteristic of the corrective opticalfilm being different in different regions of the corrective opticalfilm, the characteristic being selected from the group consisting of athickness of the corrective optical film and a curvature of thecorrective optical film, such that the corrective optical film isconfigured, upon being adhered to the single-focal lens, to change afocal length of the single-focal lens differently in different regionsof the single-focal lens.
 2. The apparatus according to claim 1, whereinthe corrective optical film is configured to convert the single-focallens to a progressive lens.
 3. The apparatus according to claim 1,wherein the corrective optical film is configured to be adhered to theoptically-corrective single-focal lens, at least partially using vacuum.4. The apparatus according to claim 1, further comprising a protectivefilm configured to protect at least one side of the corrective opticalfilm.
 5. The apparatus according to claim 1, further comprising one ormore markers configured to outline an area on the optical film thatshould not be cut.
 6. The apparatus according to claim 1, wherein thecorrective optical film comprises at least one coating selected from thegroup consisting of: an anti-glare coating layer, and an anti-scratchcoating.
 7. The apparatus according to claim 1, further comprising oneor more alignment markers configured to facilitate positioning of thecorrective optical film on the single-focal lens.
 8. The apparatusaccording to claim 7, further comprising a protective film configured toprotect at least one side of the optical film, wherein the one or morealignment markers are marked on the protective film.
 9. Apparatuscomprising: a sunglasses lens; and a corrective optical film, acharacteristic of the corrective optical film being different indifferent regions of the corrective optical film, the characteristicbeing selected from the group consisting of a thickness of thecorrective optical film and a curvature of the corrective optical film,such that the corrective optical film is configured, upon being adheredto the sunglasses lens, to change a focal length of the sunglasses lensdifferently in different regions of the sunglasses lens.
 10. Theapparatus according to claim 9, wherein the sunglasses lens isconfigured to additionally provide an optical corrective function. 11.The apparatus according to claim 9, wherein the sunglasses lens is notconfigured to provide any optical corrective function.
 12. The apparatusaccording to claim 9, wherein the sunglasses lens is configured toprovide UV protection.
 13. A method comprising: identifying aprescription for at least one lens of eyeglasses a subject, theprescription being selected from the group consisting of: a multi-focalprescription, and a progressive prescription; and generating theprescribed lens by adhering a corrective optical film to anoptically-corrective single-focal lens, such as to change a focal lengthof the single-focal lens differently in different regions of thesingle-focal lens.
 14. The method according to claim 13, whereingenerating the prescribed lens comprises generating a progressive lens.15. The method according to claim 13, wherein adhering the correctiveoptical film to the optically-corrective single-focal lens comprisesadhering the corrective optical film to the optically-correctivesingle-focal lens at least partially using vacuum.
 16. The methodaccording to claim 13, further comprising, prior to adhering thecorrective optical film to the optically-corrective single-focal lens,positioning the corrective optical film with respect to the single-focallens using one or more alignment markers.
 17. The method according toclaim 13, further comprising cutting the corrective optical film to asize that fits the optically-corrective single-focal lens.
 18. Themethod according to claim 13, wherein adhering the corrective opticalfilm to the optically-corrective single-focal lens comprises adheringthe corrective optical film to the optically-corrective single-focallens, the corrective optical film being pre-formed to match a shape andsize of the optically-corrective single-focal lens.
 19. A methodcomprising: identifying a prescription for at least one lens ofeyeglasses a subject, the prescription being selected from the groupconsisting of: a multi-focal prescription, and a progressiveprescription; and generating the prescribed lens by adhering acorrective optical film to a sunglasses lens, such as to change a focallength of the sunglasses lens differently in different regions of thesunglasses lens.
 20. The method according to claim 19, wherein adheringthe corrective optical film to the sunglasses lens comprises adheringthe corrective optical film to a sunglasses lens that additionallyprovides an optical corrective function.
 21. The method according toclaim 19, wherein adhering the corrective optical film to the sunglasseslens comprises adhering the corrective optical film to a sunglasses lensthat does not provide an optical corrective function.
 22. The methodaccording to claim 19, wherein adhering the corrective optical film tothe sunglasses lens comprises adhering the corrective optical film to asunglasses lens that provides UV protection.